SU1728013A1 - Method of controlling the feed of chips with binder into moulding machine - Google Patents

Abstract

Use: manufacture of chipboard. Summary of the Invention: The level of the mixture in the first and second forming machines 7 and 8 is continuously recorded. The first signal corrects the flow of chips from the hopper 1, and the second signals the distribution of the mixture of chips with binder between the two forming machines 7 and 8, which allows to avoid discontinuity of the feeding process. shavings. 1 il.

Description

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The invention relates to the woodworking industry and is used in the production of chipboard.

There is a known method for regulating the supply of chips with a binder to a forming machine, including dispensing chips from the hopper, dispensing chips and maintaining a predetermined relationship with the binder in volume, mixing the chips with a binder, and feeding the mixture to the forming machines of a given stream.

One of the important conditions for the production of chipboard is the need to maintain a certain ratio of chips and binder by weight.

A disadvantage of the known method is dosing by volume, which inevitably leads to errors associated with fluctuations in the amount of shredded wood per unit of volume depending on the type of wood particles, the degree of compaction and wood species. The instability of the bulk mass is observed, which leads to unequal consumption of shredded wood for the manufacture of plates, resulting in plates of different density and strength.

There is a known method for regulating the supply of chips with a binder into a forming machine, including dispensing chips from a hopper with a drive for controlling chip consumption by volume, feeding chips and a binder into a mixer, maintaining a given weight ratio of the chip and binder, mixing the chip with a binder, separating into two parts by means of an adjustable gate, the mixture is fed to the forming machines of the given flow, which carry out dosing, by the mass of the mixture leaving them.

In this method, it is more preferable for practice to maintain a given ratio of chips and binder by weight. This ratio is provided by the weighing devices installed in front of the mixer, and does not change during the operation of the mixer.

The mixture is supplied to the forming machines of each flow by means of a distribution gate, which opens or closes as the feeders of the forming machines are filled with the mixture.

Since it is impossible to accurately match the performance of the mixer and forming machines, the mixer in all cases adjusts the performance to a deliberately greater than the total performance of both forming

machines, and the coordination of their work is achieved by stopping the mixer. At the same time, chip levels in forming machines range from minimum to maximum.

The interruption of the supply of chips and the binder to the mixer occurs when the shaft is inertia, which results in a violation of the sizing quality of a certain portion of chips. The same happens

0 and when starting the mixer. Therefore, stopping the mixer is undesirable.

Chip level fluctuations in forming machines cause the following unrecoverable carpet defects: reduced

5, the accuracy of the weights of the forming machine, as the chip compaction changes dramatically, and consequently the inevitable oscillations of the weight characteristic of weights change, the filling uniformity deteriorates over the width, as the surface shape changes along with the level, which leads to a random distribution of compaction width.

The purpose of the invention is to increase the quality of the carpet being formed by uniformly filling it in width and weight, eliminating the stopping of the mixer and ensuring a more stable weight ratio of the chips and the binder during

0 of the entire process.

The goal is achieved by registering the levels of a mixture of chips and a binder in dispensers of both forming machines and by the magnitude of the signal of this level

5, in the first forming machine, the flow of chips from the hopper is adjusted, and the distribution of the chip mixture with the binder between

0 first and second forming machines.

The method is carried out as follows.

Chips from hopper 1 which has

5, the drive 2 for controlling its flow, is fed through the screw 3 to the mixer 4, the binder pump 5 is fed there, the chips are mixed with the binder in the mixer 4, and the resulting mixture

0 goes further along the conveyor 6 to the first 7 and second 8 forming machines of this stream. Forming machines 7 and 8 are made in the form of metering devices 9 with bucket weights 10, 11 and feeders 12, 13, which

5 provide uniform discharge of chips from the machine in a continuous stream to form the carpet 14.

Feed the mixture to the corresponding two

sequentially mounted forming machines 7 and 8 are divided by an adjustable gate 15 with a drive 16 into two parts. This mixture forms in surfaces of the dispensers 9 a surface 17 of a certain shape. The containers of the dispensers 9 are equipped with analog sensors 13 and 19 for maintaining the levels 20 and 21 of the bulk mixture constant. The constancy of the level in each tank provides a certain shape of the surface 17 of the bulk mixture. In the case of a mixture level deviation from a predetermined signal from the sensors, they are amplified by amplifiers 22 and 23 and have a controlling effect on the drives 2 and 16 of the bunker 1 and the gate 15, respectively. These funds are systems for automatically stabilizing the mixture levels in the first 7 and the second 8 forming machines of this flow, and the level 20 in the first forming machine is maintained by controlling the flow rate of the chips (drive 2) when it is dispensed from the hopper, and the level 21 in the second forming machine is maintained by adjusting - lation gate drive. Such an implementation (regulation) allows one to more precisely maintain the specified ratio of chips and binder by mass, regardless of changes in the entire system, to exclude the mixer stops, while the supply of binder to the mixer remains constant and does not need to be adjusted.

When using the proposed method, the process is continuous.

At a constant level of the mixture, the introduced errors from the compaction are of a systematic nature and the multiplier f.nu are filled with the appropriate subunit of the forming machines.

Since the flow rate of the forming machines is regulated by weights, the accuracy of which is increased due to the stabilization of the level, and the flow of resin into the mixer is fixed (which in itself greatly simplifies the task of batching the binder), the mixer passes through a strictly defined mass. the amount of dry chips, which is required to improve the technology.

Claims (1)

Formula Invention A method for regulating the supply of chips with a binder to a forming machine, including dispensing chips from a hopper with adjusting the volume of chips in volume, feeding chips and a binder to the mixer while maintaining a specified ratio between the masses of the chip and binder, mixing the chips with the binder , feeding the mixture to two forming machines with continuous separation of this mixture between the forming machines. that, in order to improve the quality of the formed carpet, the levels of the mixture of chips and binder are recorded in the dispensers of both forming machines and by the magnitude of the signal of this level in the first forming machine they correct the flow of chips from the bunker, and the distribution of the chip mixture is adjusted by the value of the signal of the second forming machine with a binder between the first and second forming machines.